Automatic suspension and contact appliance for electric-arc lamps.



PATENTED JAN. 3, 1905.

JQSTEVBNSGN, JR. AUTOMATIC SUSPENSION AND CONTACT APPLIANCE FOR ELECTRICARC LAMPS.

APPLICATION FILED DEC. 22, 1903.

2 SHEETS-SHEET 1.

vvrnvsssas /N\/EN TQF? No. 778,911. PATENTED JAN.3, 1905.

J. STEVENSON, JR. N AUTOMATIC SUSPENSION AND CONTACT APPLIANCE FORELECTRIC ARC LAMPS.

APPLICATION FILED DEG. 22, 1903.

2 SHEETS-SHEET 2.

WITNESSES //\/\/ENT0F? UNITED STATES Patented January 3, 1905.

JOHN STEVENSON, JR., OF PORTOBELLO, SCOTLAND.

AUTOMATIC SUSPENSION AND CONTACT APPLIANCE FOR ELECTRIC-ARC LAMPS.

SPECIFICATION forming part of Letters Patent No. 778,911, dated January3, 1905.

Application filed December 22, 1903.

1'0 all whom it may concern:

Be it known that I, J OHN STEVENSON, J r., electrical engineer, asubject of the King of Great Britain, and a resident of Rowan Bank,Durham Road, Portob'ello, Scotland, have invented an Improved AutomaticSuspension and Contact Appliance for Electric Arc Lamps and otherApparatus Requiring to be Raised and Lowered, of which the following isa specification.

This invention relates to a suspension and contact appliance forelectric-arc lamps and such like requiring to be raised and lowered; andits object is to provide means whereby when an arc-lamp or the like isdrawn up into position its weight shall be taken off the lowering andraising chain or rope and at the same time the lamp shall beautomatically connected into correct electrical circuit and its weightutilized for making a sound electrical contact.

On the drawings annexed, Figure 1 is a vertical section of the device.Fig. 2 is a horizontal section taken on the line X X and looking frombelow. Fig. 3 is an inverted plan view of the socket.

- The arrangement shown on the drawings is for three electricalcontacts.

' The device, which takes the form of adome or bell a, is secured to thelamp-pillar, preferably by means of a socket-joint b. In the dome arefour suspenders 0. two of them being shorter than the other two. Theshort suspenders are arranged opposite one another, and so also are thelong suspenders. Each suspender has a contact step or hook (Z at itslower end, and the contacts of the short suspenders are adapted toengage with the annular inverted-trough-shaped contact a of the socketf, and the contacts of the long suspenders are adapted to engage withthe annular inverted-trough-shaped contact g of the socket h. Thesockets f and It and the plug 2' are made of porcelain or otherinsulating material and are of the shape shown. Each hook (Z has ahinged shutter 7', of triangular shape and which is capable of closingor covering the hook. Above the socket f is a tubular or telescopiccontact 7c Z, provided with Serial'No. 186,224.

an inner insulating-sleeve m. The sockets are jointed together by meansof the bolt 0.

p is the raising and lowering rope for the lamp.

9 is the electric cable leading to the long suspenders c.

r is the cable leading to the short suspenders.

s is the cable leading to the central pole or contact it. The cable tfrom the lamp it passes to the tubular contact Z. The cable 0 from thelamp passes to the annular contact 0, and the cable 20 from the lamppasses to the annular contact g.

n represents bent guide-rods arranged in the dome or bell.

The action of the appliance is as follows: The dome remains in positionat the end of the swanneck ot' the lamp-pillar and is free to swivel onits socket-joint. The sockets 7" /t are raised and lowered with the lampby means of the cord 1). When the sockets and lamp are drawn up, thesockets are guided into the bell by means of the guide-rods m, and thebeveled edge of the top socket f strikes against the wedge-shaped endsof the suspenders and forces them out. At the same time the edge of thesocket strikes against the shutters j and raises them up, (see dottedlines,) so that when the lamp is again lowered the suspenders moveinward and engage with the annular trouglrshaped contacts g. Theengagement of the contacts of the suspenders with the contacts 0 gcloses the circuits. The raising of the sockets of course causes thetelescopic contacts 7 Z to engage. To disengage the contacts and lowerthe lamp, the sockets are raised sutticiently high to disengage thestep-contacts and allow the shutters to fall down and close the steps.The sockets and lamp can now be lowered, and in falling the beveled edgeof the socket itirnpinges on the inclined back of the shutters, and as aconsequence forces the suspenders back out of the way. It will be seenthat when the contacts are engaged the weight of the lamp is thrown ontothe steps of the suspenders, so that the whole Weight is utilized so asto give correct electric contact. Further, as the contacts 0 g areturned downward they are not liable to gather rain, and soshort-circuit.

Having now fully described my invention, what I claim, and desire tosecure by Letters Patent, is-

1. In a suspension and contact appliance for electric-arc lamps and suchlike requiring to be raised and lowered the combination of suspendershaving step-contacts with an insulated socket having an annularinverted-troughshaped contact therein the step -contacts of thesuspenders being adapted to automatically engage with the contact of thesocket substantially as described.

2 In a suspension and contact appliance for electric-arc lamps and suchlike requiring to be raised and lowered the combination of a bell,suspenders pivoted to the bell, contacts on the suspenders, means forconveying an electric current to the suspenders, an insulated socket, anannular inverted-troughshaped contact therein, means for electricallyconnecting the socket to the lamp or such like, and means for raisingand lowering the socket substantially as described.

3. In combination, a case, freelymoving suspenders arranged within thecase, means for conveying an electric current to the suspenders,step-contacts on the suspenders shutters for closing the steps, aninsulated socket arranged within the case an annular contact in thesocket electrically connected with an arc-lamp and means for raising andlowering the socket and lamp substantially as described.

4. In combination, a case, freely-moving suspenders arranged within thecase, means for conveying an electric current to thesuspendcrs,step-contacts on the sus1 enders,shutters for closing thesteps, insulated sockets arranged within the case and one above theother, annular contacts in the socketssaid contacts being electricallyconnected with an arc-lamp, means for securing the sockets together,andmeans for raising and lowering the. sockets and lamp substantially asdescribed.

5. In combination, a case, freely-moving suspenders arranged within thecase, means for conveying an electric current to thesuspenders,step-contacts on the suspenders,slmtters for closing thesteps, insulated sockets arranged within the case and one above theother, annular contacts in the sockets, a telescopic contact arrangedabove the sockets, said contacts being electrically connected with anarc-lamp,means for securing the sockets together, and means for raisingand lowering the sockets and lamp, substantially as described.

Signed at Glasgow this 10th day of December, 1903.

JOHN STEVENSON, JUNK.

\Vitnesses:

JNO. MoFADznAN, W ILLLUL FLEMING.

